Ice making apparatus



March 12, 1957 M. w. BAKER ICE MAKING APPARATUS Filed March 27, 1952 4Sheets-Sheet l IN VEN TOR.

BY Mamba/l M Baker March 12, 1957 w, BAKER 2,784,563

ICE MAKING APPARATUS Filed March 27, 1952 4 Sheets-Sheet 2 INVENTOR.allars/m/l W. Baker B Fig. 3 x W144 ,M%M.

March 12, 1957 M. w. B H-5R 2,784,563

ICE MAKING APPARATUS Filed March 27, 1952 4 Sheets-Sheet 5 a 34 Q Fig.5

so as 2 3 Fig. 6. l7

3:; 2 26 23 INVENTOR. Marsha/l W Baker 0 62a BY March 12, 1957 Filed March 27, 1952 M. W. BAKER ICE MAKING APPARATUS 4 sheets sheet 4 /2 Fig INV EN TOR.

Marsho/l W Baker United States Patent ICE MAKING APPARATUS Marshall W.Baker, Dayton, Ohio, assignor to General Motors Corporation, Dayton,Ohio, a corporation of Delaware Application March 27, 1952, Serial No.278,928 12 Claims. c1. 62-7)- The present invention relates to arefrigerating apparatus and particularly to an ice cube maker.

An object of my invention is to provide improvements in automatic,self-contained, compact ice cube making and storage apparatus to insureefficient operation thereof in the production of clear, sanitary icecubes.

Another object of my invention is to reduce to a minimum the interval oftime between an ice releasing operation and an ice forming operation inan ice cube making apparatus of the type which produces solid ice cubesof a size to be placed in glasses containing drinks to be chilled.

Another object of my invention is to provide an improved freezing memberfor an ice cube making apparatus wherein the low temperature employed tofreeze a layer or slab of ice thereon is concentrated and substantiallyretarded from being transmitted to other elements in the apparatus.

Another object of my invention is to provide a water distributor fordirecting a film of water over a freezing member in an ice cube makingapparatus which can be readily disassembled and removed from theapparatus .for thoroughly cleaning the same,

Further objects and advantages of the present inven- 2 tion will beapparent from the following description, reference being had to theaccompanying drawings, wherein a preferred form of the present inventionis clearly shown.

in the drawings: 7

Figure 1 is a perspective view of an ice cube maker cabinet havingportions thereof broken away to show various elements in the cabinet;

Figure 2 is an enlarged front view of the ice maker cabinet shown inFigure 1 partly in section and partly in elevation;

Figure 3 is a top view of the ice cube maker on a reduced scale with thetop cover thereof removed;

Figure 4 is an enlarged fragmentary vertical sectional view taken on theline 4-4 of Figure 3 showing a part of the ice thickness control for theice cube maker;

Figure 5 is a view of the under side of the freezing member in the icecube maker and is taken on the line 5-5 of Figure 2;

Figure 6 is an enlarged sectional view taken on the line 6-6 of Figure 5showing refrigerant passages in the freezing member;

Figure 7 is an enlarged fragmentary sectional view of a waterdistributing member in the ice cube maker and is taken on the line 7-7of Figure 2;

- element 47 disposed thereabove.

"ice

Figure 8 is a bracketed view of the water distributing memberdisassembled from the cabinet and showing end plugs removed from theheader thereof;

Figure 9 is a diagrammatic view of various elements of the ice cubemaker and shows an electrical circuit therefor;

Figure 10 is a front perspective view of a modified form of ice cubemaker;

Figure 11 is a fragmentary vertical sectional view of the modified icecube maker and is taken on the line 11-11 of Figure 10; and

Figure 12 is a fragmentary vertical sectional view taken on the line1212 of Figure ll showing an arrangement of harvesting ice cubes fromthe modified ice cube maker disclosed in Figure 10.

Referring to the drawings, for illustrating my improvements, I haveshown in Figure 1 thereof an ice cube making apparatus including acabinet comprising a bottom insulated wall 11, a back insulated wall 12,upright insulated walls 13, 14 and 15, a horizontal insulated wall 16,an insulated front wall 17 and an insulated removable cover or top wall18 forming a compartment 20 within the cabinet. Compartment 20 ishorizontally elongated at its upper portion with respect to its lowerportion and therefore extends over a noninsulated machine compartment 21provided in the cabinet. The insulated cabinet walls are of usual orconventional structure wherein the insulating material thereof isdisposed between an outer metal shell or panels and an inner metal linerfor the compartment 20. An inclined unitary freezing member, generallyrepresented by the reference character 23, is stationarily mounted,preferably at an angle of approximately 15, in the upper portion of theinsulated compartment 20 above the machine compartment 21. The freezingmember 23 includes a plate portion comprising two superimposed andbrazed together plates 26 and 27 (see Figure 6) the lower of which isembossed to provide refrigerant expansion or conveying passages 28between the plates. These plates 26 and 27 are formed of a metal of highheat conductivity such for example as brass. The marginal edges of thebrazed together plates 26 and 27 are bonded, such as by soldering thesame, to the inner edge portions 31 of a mounting frame 32 (see Figure6). Outer edge portions of mounting frame 32 along the two sides thereofare raised and flanged outwardly as at 33 and are bolted or otherwisesuitably secured to angle iron members 34 attached to the com partmentmetal liner (see Figures 5 and 6). Mounting frame 32 is preferablyformed of a material of relatively low heat conductivity such forexample as stainless steel or a suitable insulating material. By makingthe frame 32 of a material having lower heat conducting properties thanthe plate portion of member 23, better concentration of a lowtemperature is obtained and transmittal of this low temperature to otherelements is materially reduced. A metal cover 36 is also secured to theangle iron members 34 and is spaced from the plate portion of member 23.Cover 36 is provided with an opening 37 (see Figures 2, 3 and 4) whichreceives a part of a thermostatic means. This thermostatic meanscomprises a substantially U-shaped in cross-section arm 41 having itsone end pivotally secured to a bracket 42, welded upon cover 36, by apin or the like 43 (see Figure 4). The other end of arm 41 carries afeeler receptacle 44 containing a coiled tube 46 and a coiled electricalheating Heating element 47 is a one-half to five watt capacity electricheater. An adjustable lock screw arrangement, of any suitable ordesirable construct-ion, is located between the ends of arm 41 forregulating the distance between the feeler receptacle 44 and the flatface of plate portion of freezing member 23. For example receptacle 44may be adjusted to produce a slab of ice of from %-inch thickness to%-inch thickness. Tube 46 has its end at the coiled portion thereofsealed and has its other end connected to an expansible and contractableelement 49 located in a suitable or conventional electric snap switch 50(see Figure 9). The coiled heating element 47 has wire connections witha low voltage electric circuit to be hereinafter described.

Freezing member 23 forms a part of a closed refrigerating system and therefrigerant expansion or evaporating passages 28 between the plates 26and 27 of this member has a plurality of conduit connections with arefrigerant translating device. The refrigerant translating device ofthe refrigerating system is mounted within machine compartment 21 andcomprises a motor-compressor unit 51 connected by conduit 52 with acondenser -53 (see Figure 9), which may be cooled in any suitable orconventional manner. Condenser 53 is connected to a receiver 54. Aconduit 56 connects receiver 54 with the passage 28 in plate member 23.A thermostatic expansion valve 57 interposed in conduit 56 has a thermalbulb 58 and tube 59 connected thereto for operating the same as isconventional in the art. The outlet of passage 28 in member 23 isconnected, by a conduit 61, to the intake side of the compressor ofmotor-compressor unit 51. Another conduit 62 is connected with thepassage 28 in plate member 23 and this conduit extends from the top ofreceiver 54. A solenoid actuated valve 63 is interposed in conduit 62and normally closes this conduit to prevent its communication with thefreezing member 23 during refrigeration thereof. By referring to Figureof the drawings it will be noted that conduit 62 is secured to andextends around four sides of member 23 as at 62a for a purpose to behereinafter described. It should also be noted that conduit 56 issecured to conduit 62a, as at 56a, along the top and bottom sides ofmember 23 so as to provide a head exchanger for refrigerant thereinprior to its flow to and past valve 57 particularly during a freezingcycle.

Means is provided for flowing a film of water over the freezing member23. This means comprises a header in the form of a tube 66 having aplurality of aligned small holes or orifices 67 therein along its length(see Figures 7 and 8). The metal tube or header 66 also has openingstherein which fit over a pair of upstanding hollow feeder studs 68welded or otherwise suitably secured to the frame 32 of member 23, andattached thereto by screws or the like 69. The open ends of tube 66 areclosed by rubber or the like plugs 71. These plugs 71 are pressed intothe-ends of tube 66 and the upright side walls of frame 32 of member 23from a socket-like means into which the header tube 66 firmly fits. Theupright side walls on frame 32 of member 23 retain the plugs 71 in placeat the ends of tube 66 to seal its ends. Suitable washers may be placedbetween screws 69 and header 66 and between header 66 and the frame 32to prevent leakage at these points. Studs 68 each have an opening 72therein to permit water flowing from suitable supply pipes to circulateinto the header or manifold tube 66 (see Figure 7). Water supply pipes73 are connected to studs 68 in any suitable or conventional manner andthese pipes communicate with a centrifugal water pump 76 of any suitableor desirable construction located in the bottom of a water sumpreceptacle 77. An electric motor 78, below receptacle 77 and outside ofcompartment 20, is employed to operate the water pump 76. A valve 81,actuated by a float 82, controls the flow of water through a water main83 into the sump '77. A combined water strainer and flow meter 84 of anysuitable or conventional construction is interposed in main 83 torestrict the amount of water passing to valve 81.. The strainer preventsforeign matter from entering the float valve 81 and the meter part ofelement 84 permits a maximum flow rate of gallons per hour with waterpressure of 10 to 80 pounds per square inch. Receptacle or sump 77 isalso provided with a siphon pipe 86 for a purpose to be hereinafterdescribed. A relatively flat funnel-like memwater splash and this bafflemoves about its hinged support when a slab of ice is released from thefreezing member 23.

In the upper left hand portion of compartment 20 (see Figure 2) there ismounted, approximately at an angle 7% an ice dissector, cutter or grid,generally represented by the reference character 90 and which comprisesa frame 91 having sets of cross wires 92 and 93 extending in oppositedirections to one another. The set of wires 92 of this ice cutting gridare disposed above the set of wires 93 and extend in a directionparallel to the direction of travel of a slab of ice to be released frommember 23. The other set of grid wires 93 are located below wires 92 andextend transversely across the frame 91. Below icc cutter 90 there is astorage bin 96 (see Figure 1) for receiving ice cubes from the cutter90. Bin 96 is closed by a horizontal swingable insulated door 97 andaccess to ice cubes within the bin, after opening door 97, is had bypulling out the top of a hinged inner compartment or bin door 98 (seeFigures 1 and 2). Side wings provided on bin door 98 (see Figure l)prevent spilling of ice cubes from bin 96 onto the floor when door 98 isopened. A drain pipe 99 leads from the bottom of bin 96 to convey water,entering the bin from sump 77 and water from melting ice in bin 96, outof the cabinet. A thermal bulb 101 (see Figure 9) is disposed Within bin96 at a position to be contacted by and responsive to a predeterminedaccumulation of ice cubes therein. A tube 102 has its one end connectedto bulb 101 and has its other end connected with an expansible andcontractablc element, such as a bellows, mounted in a bin thermostaticswitch 103 of any desirable or conventional construction. Bulb 101, tube102 and the bellows in switch 103 are charged with a suitable fluid andthen sealed to form a temperature responsive unit for controlling theoperation of ,switch 103. A switch 105 (see Figures 2 and 3), havingcontacts 106 and 107 (see Figure 9) one of which is mounted on a movablearm 103, is associated with the ice cutter 90. Arm 108 is disposed inthe path of and is adapted to be struck and moved by a cake or slab ofice released from member 23 and slidable there-from onto the grid orcutter for a purpose to be presently described.

Electrical circuit The 115 volt power mains indicated at L and L1 leadto a low voltage, say, for example, an 11 volt transformer 116. A wire117 leads from transformer 116 to the heater 47 .of thermostatic switch50. A wire 118 leads from transformer 116 to contact 106 of switch 105.When contacts 106 and 107 are closed wire 118 leads to the other side ofheater 47 of switch 50. A resistance jumper wire 119 by-passes switch inwire 118 and continuously energizes heater 47 with approximatelyone-half watt current. This is an auxiliary feature and provides thefeeler receptacle 44 of the ice thickness thermostat with a small amountof heat to at all times insure that the interior 'therof will remaindry. A branch wire 121 leads from wire 117 to wires 92 of the ice cutter90 and a branch wire 122 leads from wire 118 to wires 93, which areconnected in series with wires 92, to continuously energize thedissector or ice severing grid 90. The wires and connections justdescribed complete the low voltage circuit incorporated in the presentice cube maker. The volt circuit includes a wire 126 branched from powermain L and leading into the bin thermostat switch 103. Another wire 127branches from power main L1 and also leads into the bin thermostatswitch 103. The wires 126 and 127 extend from switch 103 to the electricmotor of the motor-compressor unit 51 to cause continuous operation ofthis unit, which is interrupted only by actuation of switch 103 inresponse to a predetermined accumulation of ice cubes within the storagebin 96. A branch wire 128 leads from wire 127, between switch 103 andunit 51, and is connected to a movable arm 129 of the ice thicknessthermostat switch 50. A second branch wire 131 leads from wire 126,between switch 103 and unit 51, and is connected to a wire 132 whichenters one side of a solenoid in valve 63. Wire 132 extends to the waterpump motor 78. A wire 133 extends from pump motor 78 and is connected toa contact 134 of the ice thickness thermostat switch 50. The othercontact 136 of switch 50 is connected by a wire 137 with the solenoid invalve 63. The contact on arm 129 of switch 50 is adapted to alternatelyengage or disengage the contacts 134 and 136 in response to temperatureconditions in the feeler receptacle 44 associated with the freezingmember 23.

Operation Assuming that the ice cube maker is properly connected to asource of water supply, to a drain and its electrical circuit is nowenergized by plugging an extension cord, leading from the cabinet, intoan electrical outlet. Electric current flows from the mains L and Lithrough switch 103 to the motor-compressor unit 51 to cause operationthereof. Simultaneously therewith electric current flows fromtransformer 116 through wires 117 and 118 and branch wires 121 and 122to continuously energize the ice cutter 90 by directing 30 to 35 wattsof current into the resistance wires 92 and 93 to heat these wires. Asmall amount of current, one-half watt, flows through by-pass resistance119 to the heating element 47 in the ice thickness feeler member orreceptacle 44. At this same time electric current also flows throughwire 128, arm 129, of the ice thickness thermostat switch 50, contact134, then through wire 133 to water pump motor 7 8. The circuit iscompleted back to power main L from motor 78 through wires 132, 131 and126. Water fills receptacle 77 to a predetermined level under control offioat valve 81. Solenoid valve 63 is closed while motor 78 operates. Thepump 76 lifts water, from receptacle 77, by Way of the pipes 73, intoheader 66. Water is distributed in the form of a film upon the freezingplate portion of member 23 by the plurality of distributing orifices 67.The compressor of unit 51 withdraws refrigerant vapor from the passages28 in the plate portion of freezing member 23, to cause chilling of thispart of the freezing member, compresses the same and forwards thecompressed refrigerant to condenser 53 Where it is cooled and liquefiedin any suitable manner, such as by circulating room air over thecondenser. Refrigerant liquefied in condenser 53 fiows into receiver 54where it is further cooled and collected. Liquid refrigerant entersconduit 56 and flows through the portions 56a thereof to expansion valve57. Liquid refrigerant is directed into the passage 28 of member 23,

by expansion valve 57, where it vaporizes, in removing heat from theplate portion of this member, and the evaporated refrigerant is returnedthrough conduit 61, to the compressor of unit 51. The refrigeratingeflect produced by member 23 causes water from the film thereof flowingover its plate portion to freeze and accumulate thereon in the form of alayer or slab of ice. When the thickness of the layer or slab of ice onmember 23 reaches the feeler receptacle 44 its temperature overcomes thesmall amount of heat imparted, by resistor 119, to heating element 47and cools the coiled portion of tube 46. When the temperature of tube 46is lowered to the desired point, in accordance with a predeterminedthickness of accumulation of ice on member 23 element 49 of switch 50will contract and cause movement of switch arm 129 away from contact 134and into engageter per hour from the receptacle.

.3 ment with contact 136. When'arm 129 disengages contact 134, of switch50, the circuit to water pump motor 78 is broken or opened and when thisarm engages contact 136 the circuit to the solenoid valve 63 is made orclosed. Energization of the solenoid in valve 63 causes valve 63 to openand hot gaseous refrigerant is therefore circulated from the receiver 54and condenser 53, through conduit 62, conduit portions 62a and thencethrough the passage or passages 28 in the freezer plate portion ofmember 23 and thereafter back to the compressor of unit 51 whichcontinues to operate. The hot refrigerant gas first warms all four sidesof freezing member 23, by flowing through conduit portions 62a, andthereafter warms inner portions thereof by its flow through passages 28.The thermostatic switch 50 therefore serves as a means responsive to apredetermined accumulation or thickness of ice on member 23 tosimultaneously stop the flow of water over the freezing plate, to renderthe refrigerating means ineffective and torender the heating means, hotrefrigerant gas line 62, effective. Heat of the gaseous refrigerantflowing around the edges of the plate portion of member 23 and throughthe refrigerant passages 28 therein melts and breaks the bond betweenthe slab of ice previously formed on member 23. This released slab ofice moves otf the inclined freezing member 23 by sliding therefrom ontothe inclined ice dissector or severing grid 90.

As soon as the water pump motor 78 stops operating, water flowing overthe member 23 and water contained in the pipes 73 drains into the sumpor receptacle 77 to raise the level of the body of water therein to apoint above the uppermost portion of siphon pipe 86. This renders thesiphon pipe 86 effective and substantially all of the water in the watersump is siphoned out of receptacle 77.' The siphon pipe 86 is made largeenough with respect to the rate of flow of water into receptacle 77,through valve 81, and with respect to the flow of water through meter 84that the water contained in receptacle 77 when pump 76 stops iswithdrawn from the receptacle at a much greater rate of flow than thatwhich water can enter the same. For example, when float valve 81 isopened wide, meter 84 permits only 14 gallons of water per hour to enterreceptacle 77 while siphon pipe 86 is capable of removing 90 to gallonsof wa- Valve 81 insures an adequate supply of Water in receptacle 77,for circulation to the water distributing header 66, under normalconditions or during a freezing cycle while siphon pipe 86 insures thedrainage of substantially all water from the receptacle 77 after eachfreezing cycle. The draining of water from receptacle 77, after eachfreezing cycle, removes minerals from receptacle 77 and conveys the samedown the pipe 86 to bin 96 and through drain pipe 99 to thus insure theproduction of pure, glistening clear ice cubes at each freezing cycle.

As the slab of ice slides onto grid 90 it strikes the movable arm 108 ofswitch and causes the contact 107 carried thereby to engage contact 106.Closing of contacts 106 and 107 causes the flow of about 5 watts ofelectric current, around resistor 119, through wires 117 and 118 to theheating element 47 of the ice thickness thermostat. Heat generated bythe electric heating element 47 rapidly warms the coiled portion of tube46 to thereby cause expansion of element 49 of switch 50. This providesa means of reducing the time between the removal of a slab of ice frommember 23 and a subsequent ice slab freezing cycle since the arm 129 ofswitch 50 will be quickly moved to engage contact 134, after the slab ofice leaves the member 23. In other words the interval of time between awarming cycle and a refrigerating cycle is reduced to a minimum toinsure rapid production of ice cubes. Movement of arm 129 away fromcontact 136 of switch 50 deenergizes the solenoid valve 63 to causeclosing thereof and the engagement of arm 129 with switch contact 134again greases energizes the water circulating pump motor 78. Heat of theone set of wires 92 in grid 90 cuts, dissects or severs the slab oficereceived thereby and resting thereon into a plurality'of long narrowslabs which fall through the space between wires 92 onto the set ofwires 93. The heat of wires 93 theafter cuts, dissects or severs theplurality of long narrow slabs of ice resting thereon into a pluralityof ice cubes or cubelets which fall through grid 90 intothestorage bin96. The size of the ice cubes or cubelets is 1% inches by 1 /2 inchesand of a thickness between inch and inch as determined by the adjustmentof the distance between feeler receptacle 44 and the flat top of member23. These ice cubes or cubelets can then be harvested from the cabinetby opening the insulated door 97 and bytilting the inner bin door 98forwardly as shown in Figure 1 of the drawings. The freezing cycles andthe ice releasing cycles continue until such time as the storage binbecomes substantially full of ice cubes. When ice cubes accumulate inbin 96 to the point where they will contact the bin thermostat bulb 101the bin thermostat switch 103 is actuated to open the electric circuitleading to motor-compressor unit 51 and other elements in the 115 voltcircuit of the ice cube maker. Operation of the ice cube maker will bere-established automatically after a sufiicient number of ice cubes havebeen removed from the storage bin thereof or have melted so as to lowerthe level of the ice cubes below the thermostat bulb 101.

Should the orifices 67 of water distributing header or manifold 66become clogged with foreign matter or corroded the header 66 togetherwith its end plugs are removed from its retaining socket means, member23. This is done by removing the screws 69 and lifting upward on headertube 66 to slide the same, with its end plugs intact, off its upstandingfeeder mounting studs 68. Thereafter the plugs 71 are removed from tube66 to open both ends thereof (see Figure 8) whereupon a bottle or thelike cleaning brush may be inserted into, passed through andreciprocated within the tube 66. Any dirt, foreign matter or corrosionin the vicinity of holes or orifices 67 will be removed and the waterdis tributing member may thereafter be reassembled.

In Figures 10, 11 and 12 I show a modified arrangement for collectingand harvesting ice cubes produced in a cube maker of the type hereindisclosed. In this modified showing, the ice cube maker 140 is providedwith a horizontal hinged door 141 which closes an opening 142 (seeFigure 11) in the front of the cabinet. Behind door 141 there isdisposed two horizontally spaced apart removable trays or the like 143(see Figure 12) mounted upon a support 144. Support 144 has openings 146therein at the sides of trays 143. A large storage tray 147, having afront member 148 closing another opening 149 in the front of cabinet 140(see Figure 11), is

supported upon tracks 151 located at the bottom of the storage bin. Inthis form of my invention ice dissected or cut into cubes by grid 90fall into the trays 143. These trays 143 may be removed and employed asserving trays as frequently as desired to thus eliminate the necessityof a waiter or waitress scooping up the ice cubes in a serving scoop ortray. The ice trays 143 may be left in position in the cabinet and uponbeing filled with ice cubes additional ice cubes dropping from grid 90will overflow the trays 143 and fall through the openings 146 in support144. The extra or additional overflowing ice cubes drop into the tray147 where they may be stored until a demand therefor arises. Means suchas the bin thermostat switch 101 shown in Figure 9 of the drawings maybe provided to prevent continued pro duction and accumulation of icecubes in tray 147 in this modified form of apparatus if desired.

From the foregoing it should be apparent that I have provided a sanitaryice cube maker or apparatus which produces, automatically, largequantities of solid crystal clear ice cubes or cubelets. By warming theice thickness responsive thermostat switch as soon as a slab of ice isremoved from the freezing member of the apparatus I reduce the period oftime between an effective freezing cycle and an ice slab removing cycleto a minimum. Also by providing the ice thickness thermostatic meanswith an adjustment the thickness of ice cubes or cubelets produced bythe present apparatus may be varied. Since the ice cutter or dissectoris continuously energized it is at all times ready to receive a slab ofice from the freezing member and effective to cut or sever the slab ofice into a plurality of ice cubelets or cubes. 7

While the form of embodiment of the invention as herein disclosedconstitutes a preferred form, it is to be understood that other forms mi'ht be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. An ice making apparatus comprising, a cabinet, a plate within saidcabinet, means for flowing water over said plate, means forrefrigerating said plate to freeze water flowing thereover into a slabof ice thereon, means for heating said plate, said plate heating meansbeing normally ineffective during refrigeration of said plate and whilewater is flowing thereover, thermostatic means responsive to apredetermined thickness of the slab of ice formed on the plate tosimultaneously stop the flow of water over said plate, to render saidrefrigerating means ineffective and to render said heating meanseffective for breaking the bond between the slab of ice and the platewhereby the slab of ice slides off said plate, means within said cabinetfor receiving the slab of ice slid 01f said plate and for dissecting thesame into a plurality of ice blocks, means for applying heat to saidthermostatic means, and means actuated solely in response to the slab ofice engaging same as it slides off said plate for controlling said heatapplying means.

2. An ice making apparatus comprising, a cabinet, a plate within saidcabinet, means for flowing water over said plate, means forrefrigerating said plate to freeze water flowing thereover into a slabof ice thereon, means for heating said plate, said plate heating meansbeing normally inelfective during refrigeration of said plate and whilewater is flowing thereover, thermostatic means responsive to apredetermined thickness of the slab of ice formed on the plate tosimultaneously stop the flow of water over said plate, to render saidrefrigerating means ineffective and to render said heating meanseffective for breaking the bond between the slab of ice and the platewhereby the slab of ice slides off said plate, means within said cabinetfor receiving the slab of ice slid off said plate and fordissecting thesame into a plurality of ice blocks of predetermined size, means forapplying heat to said thermostatic means, means actuated solely inresponse to the slab of ice engaging same as it slides off said platefor controlling said heat applying means, and said thermostatic meansbeing adjustable toward and away from said plate to vary the thicknessof a slab of ice to be formed thereon whereby ice blocks of a differentsize than said first named ice blocks can be produced by said apparatus.

3. An ice making apparatus comprising, a cabinet, a plate within saidcabinet, means for flowing water over said plate, means forrefrigerating said plate to freeze water flowing thereover into a slabof ice thereon, means for heating said plate, said plate heating meansbeing normally ineffective during refrigeration of said plate and whilewater is flowing thereover, thermostatic means responsive to apredetermined thickness of the slab of ice formed on the plate tosimultaneously stop the flow of water over said plate, to render saidrefrigerating means ineffective and to render said heating meanseffective for breaking the bond between the slab of ice and the platewhereby the slab of ice slides off said plate, means within said cabinetfor receiving the slab of ice slid off said plate and for dissecting thesame into a plurality of ice blocks, means continuously applying apredetermined amount of heat to said thermostatic means, and meansactuated solely in response to the slab of ice engaging same as itslides off said plate for increasing the supply of heat to saidthermostatic means above said predetermined amount continuously appliedthereto.

4. An ice making apparatus comprising, a cabinet, a plate within saidcabinet, means for flowing water over said plate, means forrefrigerating saidplate to freeze water flowing thereover into a slab ofice thereon, means for heating said plate, said plate heating meansbeing normally ineffective during refrigeration of said plate and whilewater is flowing thereover, thermostatic means responsive to apredetermined thickness of the slab of ice formed on the plate tosimultaneously stop the flow of water over said plate, to render saidrefrigerating means ineffective and to render said heating meanseffective for breaking the bond between the slab of ice and the platewhereby the slab of ice slides off said plate, means within said cabinetfor receiving the slab of ice slid off said plate and for, dissectingthe same into a plurality of ice blocks of predetermined size, meanscontinuously applying a predetermined amount of heat to saidthermostatic means, means actuated solely in response to the slab of iceengaging same as it slides off said plate for increasing the supply ofheat to said thermostatic means above said predetermined amountcontinuously applied thereto, and said thermostatic means beingadjustable toward and away from said plate to vary the thickness of aslab of ice to be formed thereon whereby ice blocks of a different sizethan said first named ice blocks can be produced by said apparatus.

5. An ice making apparatus comprising in combination, a substantiallyflat plate, means for circulating water over said plate, means forrefrigerating said plate to freeze water circulated thereover into aslab of ice thereon, means for heating said plate, control meansmaintaining said plate heating means ineffective while saidrefrigerating means and said water circulating means are effective,another control means substantially concurrently stopping said watercirculating means, rendering said refrigerating means ineffective tocool said plate and rendering said heating means effective to break thebond between the slab of ice and said plate whereby the slab of iceslides off said plate, and means actuated solely in response to the slabof ice engaging same as it slides off the plate for causing operation ofone of said control means.

6. An ice making apparatus comprising in combination, a substantiallyflat plate, means for circulating water over said plate, means forrefrigerating said plate to freeze water circulated thereover into aslab of ice thereon, means for heating said plate, control meansmaintaining said plate heating means ineffective while saidrefrigerating means and said water circulating means are effective,another control means substantially concurrently stopping said watercirculating means, rendering said refrigerating means ineffective tocool said plate and rendering said heating means effective to break thebond between the slab of ice and said plate whereby the slab of iceslides off said plate, an electric circuit for said means, a normallyopen switch, and means associated with said switch and engageable by theslab of ice as it slides off the plate for closing same and causingoperation of one of said control means to govern the flow of electriccurrent through said circuit to said water circulating, said heating andsaid refrigerating means.

7. An ice making apparatus comprising in combination, a plate having aninclined flat surface, means for circulating water over the inclinedflat surface of said plate, means for refrigerating said plate surfaceto freeze water circulated thereover into a slab of ice thereon, controlmeans for heating said plate, actuatable means maintaining said plateheating means inefiective while said refrigerating means and said watercirculating means are effective, an-

lower end of said plate for dissecting the slab of ice slid off same,and means actuated solely in response to the slab' of ice engaging sameas it slides off the plate for causing operation of one of said controlmeans.

8. An ice making apparatus comprising in combination, a plate, means forflowing Water over said plate, means for refrigerating said plate tofreeze water flowing thereover into a slab of ice thereon, meansresponsive to a predetermined thickness of the slab of iceformed on saidplate for effecting release of the slab of ice from said plate andmovement thereof from the plate, an electrically heated grid forreceiving the slab of ice as it moves from said plate, said griddissecting the slab of ice into a plurality of ice blocks and releasingthe ice blocks from said grid, means for receiving and collecting theice blocks released from said grid, means rendered effective in responseto a predetermined accumulation of collected ice blocks for renderingsaid refrigerating means inoperative, and means for continuouslyenergizing said grid irrespective of the effectiveness orinefiectiveness of said last named means.

9. An ice cube making apparatus including an inclined freezing plate,means for refrigerating said plate to form ice thereupon, an ice cubecutting device positioned to receive a slab of ice sliding by gravityfrom said freezing plate, 'a pump means for distributing water on saidfreezing plate, a circuit controlling said pump means, athermostatically operable element supported above said freezing plateand designed for actuation when a slab of ice of predetermined thicknessis formed on said plate, a switch means in said circuit controlled bysaid thermostatic element to stop said pump when an ice slab of apredetermined thickness is formed, a heating element adjoining saidthermostatic element for artificially heating the same, and switch meansactuated by said slab of ice and a circuit including said last namedswitch means and said heating element to heat the thermostatic elementupon closing of said last named switch.

10. An ice cube forming device including an inclined freezing plate, aninclined ice cube cutting device positioned to receive a slab of icesliding by gravity from said freezing plate, a pump for pumping waterover said freezing plate, a thermostatic element supported above saidfreezing plate and actuated upon the building up of a slab of ice onsaid freezing plate of a predetermined thickness, 21 first switchactuated by said thermostatic element, a circuit including said firstswitch and said pumping unit to stop said pumping unit when said iceslab is of predetermined thickness, a heating element adjoining saidthermostatic element, a switch upon said ice cutting device in the pathof movement of a slab of ice moving onto the same, and a second circuitincluding said last named switch and said heating element andfunctioning to energize said heating element upon movement of the slabof ice onto said cutting device.

11. An ice making apparatus comprising, a plate, means for flowing waterover said plate, means for refrigerating said plate to freeze waterflowing thereover into a slab of ice thereon, means for heating saidplate to break the bond between the slab of ice and the plate and tocause the slab of ice to slide off said plate, 'a thermostatic elementresponsive to a predetermined thickness of the slab of ice formed on theplate controlling at least one of said means, means for adjusting saidthermostatic element toward and away from said plate to vary thethickness of a slab of ice formed thereon, and means hingedly supportingsaid thermostatic element whereby said element is free to swing awayfrom said plate during sliding movement of a slab of ice on said plate.

12. An ice making apparatus comprising in combination,'an insulatedhousing, a substantially flat plate mounted in an inclined positionWithin the upper region of said housing, means for circulating a filmofwater downwardly across said plate, means for refrigerating said plateto freeze Water circulated thereacross into a layer of ice thereon,means for heating said plate to break the bond between the layer of iceand the plate to release the layer of ice therefrom in the form of aslab, a grid in said housing adjacent said plate for receiving the slabof ice released therefrom and for dissecting same into a plurality ofice pieces, a stonage bin below said grid within the lower region ofsaid housing for receiving the dissected ice pieces,-

a thermostatic element associated with the side of said plate upon whichthe layer of ice is frozen, said thermostatic element being responsiveto a predetermined thickness of the layer of ice formed on said platefor controlling at least one of said means, said thermostatic elementbeing pivotally mounted for movement away from said side of said plateas a slab of ice is-released therefrom, and riieans for adjusting saidthermostatic element relative to said side of said plate to vary thethickness of a layer of ice formed thereon whereby to change the size ofice pieces dissected by said grid.

Barrath Aug. 12, 1902 Zavarkin Oct. 29, 1918 12 Thomson Mar. 5, 1929Taylor Dec. 8, 1936 Buchanan Oct. 25, 1938 Potter' Nov. 12, 1940Schwimmer May 12, 1942 Langgaard June 23, 1942 Osborn Nov. 21, 1944Jones Aug. 7, 1945 Williams Mar. 12, 1946 Pfeil May 13, 1947 Pfeil May4, 1948 Kubaugh July 6, 1948 Crider Nov. 29, 1949 Munshower Oct. 17,1950 Gaul Mar. 27, 1951 Leeson Apr. 17, 1951 Cobb July 24, 1951 BinderNov. 6, 1951' Roberts Nov. 20, 1951 Pownall May 27, 1952 Drake Apr. 7,19 53 Leeson July 21, 1953 Kattis Sept. 1, 1953 Ayres June 29, 1954Hamlin Aug. 10, 1954 OTHER REFERENCES

